Oooo... That's an excellent twist. Make the Ori into Ancients who got possessed by Goa'uld, who then ascended, putting them beyond the reach of Ancient weapons and any simple (by the Ancient's standards) biological techniques to de-Goa'uld a host. That would make the Ori demand for worship a no-brainer without having to re-invent an excuse to fall back on the "evil aliens pretend to be false gods" idea.

It could've also served to give the Ori some actual personality, even a personal focus on SG-1 members.